Filter.



No. 656,043. Patented Aug. I4, |900.

W. PATEHSON.

FILTER.

(Application led Oct. 20, 1899.)

(No Model.) 2 Sheets-Sheet l,

wif/765565' I L@ @f 5y /I'e Patented Aug. I4, |900. W. PATERSUN.

F I L T E R.

(Application filed Oct. 20, X899.)

(No Modal.)

Wag/7663625 UNITED STATES PATENT OFFICE.

WILLIAM IA'IERSON, OF LONDON, ENGLAND.

FILTER.

SPECIFICATION formingpart of Letters Patent No. 656,043, datedAugust 14, 1900. Application filed October Z0, 1899 Serial No. 734,258. (No model.)

Tom/ZZ whom, it may concern,.-

Be it known that I, WILLIAM PATERsoN, engineer, a subject of the Queen of Great Britain, residing at 14 Killarney road,Wands worth, London, England, have invented eertain new and useful Improvements in Filters, of which the following is a specification.

This invention relates to improvements in filters for filtering liquids, and has for its objects to utilize the increased pressure exerted by the liquid to be filtered on the filter-bed when the latter is foul or silted up and to automatically operate means whereby the iiow of the liquid through the filter-bed is reversed, the filter-bed cleansed, and the filtering again started after such cleansing.

The essential feature of my invention consists in arranging a valve or equivalent dcvice in .connection with the filter-inlet or in connection with the filter inlet and outlet in such manner that when either the pressure on the inlet side of the filter or the excess of pressure at the inlet side of the filter over the pressure at the outlet side thereof exceeds a certain predetermined amount the said valve will open automatically and actuate means whereby the direction of the iiow of liquid through the filter will be reversed and the filter opened to a drain-pipe for the purpose of cleansing the lter-bed and that when the pressure on the inlet side of the filter is relieved the said valve will close again automatically and cause the fiow of liquid through the filter to be again reversed and the filtering operation to proceed.

In order that myinvention may be clearly understood and readily carried into effect, I will now proceed to describe the same more fully in connection with the accompanying drawings, in which- Y Figure l is a sectional elevation of a iilter constructed according to myinvention. l Fig. 2 is a sectional elevation ot' a iilter, showing a modified form of my invention. Fig. 3 shows a side view and a longitudinal section of the distributing-valve shown in Figs. l and 2 drawn to a larger scale. Fig. 4 is an end View of the reversing-valve and its connections drawn at right angles to Fig. 2.

y The same letters of reference indicate like parts in all the figures.

Referring to Fig. 1, A is a closed filtercasing.

B is a filter-bed supported in the said casing by a plate a.

a is a chamber below the filter-bed B, and

a2 is a chamber above the said filter-bed.

u, and a4 are respectively a deflecting-plate and a baiile-hood situated in the chamber u." of the filter.

` ci is a vertical stand-pipe which passes through the filter-bed B and connects the chambers d and a2.

C is a duid-inlet pipe to the filter, and D is the outlet-pipe for filtered liquid.

d is a collecting-pipe which is situated in the lower part of the filter-bed and connected to the oiitlet-pipe D.

y d' fl are collecting-cups which project from the pipe d.

(Z2 is a flap-valve in the pipe D, and (Z3 is a hole or aperture in the Hap-valve d2.

E is a waste-pipe leading from the chamber a'.

F is a valve comprising a plugf, a spring f, which tends to hold the plugf to .its seat, and a screw f2, by the adjustment of which the compression of the springf, and consequently the load on the valve f, may be regulated.

Gis a pipe connecting the Valve F with the inlet side of the filter.

H is a chamber arranged to receive any liquid passing through the valve F.

I is a fioat-chamber arranged below` the chamber il, and h is a Siphon adapted to rapidly transfer the liquid contents of the chamber Il into the chamber I when the chamber H has been filled by the valve F.

i is a float which is situated in the chamber I and is provided with a stem or rod fr".

i2 is a siphon for emptying the float-chamber I after the latter has been iilled.

'i3 is a valve or cock by the adjustment ot' IOO an annular recess between them. The pipe C communicates with the cylinder .T by means of ports c and c'.

K is a closed cylinder in which a piston 7: is adapted to slide.

e is a valve controlling. the outlet of the waste-pipe E.

j is a rod connecting the slide-valvej= the piston 7:, and the valve e.

M is adistributing-valve, and mis the chamber in which the valve M slides. The valve M consists of two disks or junks m' and m2, having a central annular recess between them, and '1n3 is a central longitudinal waste or exhaust channel which passes through the valve M and connects the opposite sides of the valve-chamber m.

m4 and m5 are ports or passages respectively connecting the ends of the cylinderK with the opposite sides of the valve-chamber m.

on is a central port in the valve-chamber on., and N is a pipe connecting the port m6 with the inlet-pipe C at a point ou the far side of the valve-cylinder or 'with other suitable pressure source.

on? is the waste or exhaust outlet from the valve-chamber on.

ms isa valve-rod one end of which is conneeted to the valve M. This valve-rod 'mB passes through the lower end of the valvechamber m and has its lower end connected by a rod O to one end of a rocking lever P. The rocking lever P is pivoted at p to a projection on the float-chamber I and has its opposite end attaehedby a pin-and-slot connection to the float-stem t".

Q is a float situated in the chamber a2.

q is a rod connecting the float Q to a valve q.

'q2 is a seat for the valve q', and q3 is an opening or port in the casing A controlled by the valve q The filter operates as follows: The tension of the springf is adjusted so as to keep the valve-plug f closed to its seat against the pressure of the liquid in the inlet-chamber a2, so that when th'e filter-bed B is clean the chambers H and I are empty, the valves M, 1', and e are in the positions shown, and the upper side of the piston lo is open to the fluid-pressure through the port N, port m6, annular passage in the valve M, and port m5, and the lower side of the piston 7c is open to exhaust through the port m", chamber m, and the exhaust or waste m7. The liquid to be filtered then passes under pressure through the port c, the annular passage in the valve j, the port c', and pipes C to the ilter-cham ber a', and thence up through the stand-pipe a5 and down through the filter-bed, and is then collected by the cu ps d d and conducted away through the filtered-water outlet-pipe D to a suitable receiving vessel or reservoir, the force of the upward flow of the filtered liquid being sufficient to raise and pass by the flap-valve d2.

When the filter-bed becomes silted up or foul, it offers a greater resistance to the passage of the liquid to be filtered, so that the pressure in the chambers a and a? is increased. This increased pressure is communicated by the pipe G to the valve f, and when the said pressure becomes suicient to overcome the load exerted by the spring f on the valve f the valve f will be raised and liquid will be permitted to pass from the chamber a2 through the pipe G and valve F into the chamber H. Directly the chamber His filled to the required point the siphon h comes into operation 'and rapidly transfers the liquid from the chamber H to the chamber I, thereby raising the float 1'., rod 1l', and the end of the lever P which is attached` to the rod il and lowering the opposite end of the lever P. This movement of the lever P is communicated by the connecting-rod O and valve rod ma to the distributing-valve M,which latter is thereby drawn down or reversed, so as to put4 the upper side of the piston 7a to exhaust o'r waste through the port m5, valvechamber m, waste-channel m3 in the valve M, and exhaust or waste port m", and to open the lower side of the piston k to the fluidpressure'through the port m4, annular passage in the valve M, and pipe N. The piston k is thereby raised, and as it is fixed to the valve-rod 7'3 the valve j will be also raised, so as to close the port c, and the waste-valve e will be opened. The filtered liquid will then flow back through the pipe D and entering the filter-bed'B through the cups d' d' will loosen and wash the filtering medium, overflow into the stand-pipe a5, land then pass away through the waste-pipe E, carrying the impurities with it. When the flow of liquid through the filter is thus reversed by closing the inlet and opening the waste-pipe, the pressure within the filter is reduced and the valve f is again closed by the spring f', and when the chamber I has been emptied by the Siphon 2 the float i will fall, thereby again reversing the valve M to the position shown in Fig. 1, when the lower side of the cylinder K is open to the Vwaste m7. through the port *rn4 and chamber m and the upper side of the piston k is open to the fluid pressure, so that filtering will again proceed.

Although liquid may only escape slowly through the valve F, yet, owing to the fact that the siphon h rapidly tranfers the contents of the chamber H tothe chamber I th'e oat 1l is rapidly raised, and the action of the filter is reversed by a quick and decisive movement of the distributing-valve M.

The length of time for which the cleansing or reversed flow of liquid is permitted to pass through the filter obviously depends upon the length of time that the float i remains raised. This can be regulated, as aforesaid, by adjusting the cock i3 of the siphon so as to empty the chamber I more or less rapidly.

It is not advisable that the force of the reversed or cleansing flow of liquid through the filter should be so great as to wash away some IOO of the filtering medium into the waste-pipe. 'lo obviate this, the filtered liquid when reversed closes the valve d2 and can then pass only through the passage d, which is of less sectional area than that of the pipe D.

The float Q is kept in its raised position by the pressure in the filter while filtering is proceeding, andthe valve q' is held to its seat q2. \Vhen the supply-inlet is shut off and the waste is opened, as above described, however, the pressure within the filter is relieved and the float (2 is permitted to fall, thus open-l ing the valve q and permitting the external atmospheric air to enter the filter through the opening or port ([3.

Referring to Figs. 2 and t, the filter-bedB rests upon a suitably-perforated plate or its equivalent c6. The stand-pipe a5 is omitted, as are also the collectingcups df. The outletpipe D for the filtered liquid leads from the filter-chamber a' to a port d" in the valvecylinder J. D is a pipe connecting the lower end of the cylinder J with the filtered-liquid reservoir. E is a waste-pipe leading from the upper end of the cylinder J. The lever l) in this case has its end at one extremity pivoted atp to the frame supporting the chamber H, its end at the opposite extremity being connected to the rod O, and the float-stem t" being attached to it at an intermediate point by a pin-and-slot connection. The valve F is in this case constructed as an equilibrium valve, as follows: The plug f, provided with a suitable seat, has a stem f3, which passes fluid tight through a chamber fi, then through a closed cylinderf", and has its upperend attached to one end of a rocking lever This rocking lever f is pivoted atfG to an arm projecting from the cylinder f4 and has its other end attached to one end of the springf'. The other end of the springf is secured to an arm f7, which projects lfrom the cylinder f4. fgf2 are nuts for adjusting the tension of the springf. fs is a piston which is arranged so as to be capable of sliding in the cylinder]c4 and is fixed to the valve-stem f3. R is a pipe connecting the chamber a2 of the filter with the upper end of the cylinder' f4, and S is apipe connecting the chamberct' of the filter with the lower end of the cylinder f4. T is aliquid-supply pipe connecting the valve-chamberf* with anysuitable source of liquor under pressure.

In Fig. 2 the fioat-valve Q is constructed and operates substantially as above described with reference to Fig. l.

It is obvious that in order that. the filtering may proceed the pressure in the chamber a2, into which the liquid to be filtered fiows, must be greater than the pressure in the chamber a', from which the filtered liquid is withdrawn. The pressure conveyed through the pipe R and acting on the upper side of the piston f8 is therefore greater than the pressure `conveyed through the pipeS and act-ing upon the lower side of the piston f8. This difference between the pressures on the rejusted that when the filter-bed 13 is clean the valve f is held to its seat. The chambers 1I and I are then empty and the valves f, M, and 7' are in the positions shown in Fig. 2. The liquid to be filtered then enters the cylinder J by the port c, passes around the annular passage in the valve j, and thence through the port c to the chamber (t2 of the filter. The liquid then passes through the filter-bed l into the chamber a and then through the pipe D and port CZ" into the lower end of the cylinder J, below the valve j. From this lower end of the cylinderJthe filtered-liquid is conveyed by the pipe D to the filtered liquid reservoir. When the filter-bed becomes foul or silted up, increased pressure is required to force the liquid through the filtering medium, so that the pressure inthe chamber a2 increases, while the pressure in the chamber ct in the outlet side of the filter-bed may not increase. The pressure conveyed through the pipe R and acting on the upper face of the piston f8 is therefore increased, while the pressure conveyed through the pipe S and acting on the lower face of the piston f8 may not beincreased. When this increase in pressure in the chamber a2 reaches a given point, (which point is determined by the degree of tension of the springf) the piston f8 and valve-stein f3 will be automatically lowered, the valve f opened, and liquid permitted to pass from the pipe T into the chamber II. The siphon 71., fioat t', siphon t2, and lever P will operate as previously described, the connecting-rod O and valve-stein m8 being raised and the valve M reversed, so as to open the upper face of the piston la to the duid-pressure through the port m6, annular passage in the valve M, and port m5 and to put the lower face of the piston 7c to waste through the port m4, chamber m, and port m7. The piston 7c and valve-rod ,js are thereby lowered and the valve j reversed, so as to connect the ports cand di through the annular passage in the valvej to close the pipe D and to connect the port c with the wastepipe Et. The unfiltered liquid then passes through the port c, annular passage in the valve j, and pipe D into the chamber a', and thence up through the filtering medium into the chamber a2, through the port c', and upper end of the cylinder J to the waste-pipe E', the filter-bed being thereby loosened and Washed and the impurities carried away. When the fioW of liquid is thus reversed, the lpressure in the chamber a2, and consequently upon the upper face of the pistonf8,decreases. The springf then closes the valve f. When the chamber l has been emptied by the siphon i2, as previously described, the fioat 1I falls, the valve M is reversed, so as to put the upper face of the piston 71: to waste through the port m, chamber m, valve-channel m3,

IOO

IIO

and port m", while the lower face of the piston 7c 'is again opened to fluid pressure through the port m, annular passage in the valve M, and port m5. The valvej is thereby again raised tothe position shown in Fig. 2 and the filtering proceeds.

1. In a filter the combination with the filterbed,the unfiltered-liquid inlet, the filteredliquid outlet and the waste-pipe, of means operated by the increase in the difference of the pressure between the inlet side of the filter and outlet side of the filter when the filterbed becomes foul, whereby the fiow of liquid through the filter is automatically reversed substantially as described, for the purpose specified.

2. In a filter the combination with the filterbed,the unfiltered-liquid inlet, the filteredliquid outlet andthe waste-pi pe, of means operated by the increase in the difference of the pressure between the inlet side of the filter and the outlet side of the filter when the filter-bed becomesfoul, whereby the flow of liquid through the filter is automatically reversed so as to cleanse the filter-bed, and the filtering operation automatically restarted after the filter-bed has been cleansed, su bstantially as described.

3. In a filter the combination with the filter-bed the unfiltered-liquid inlet, the filteredliquid outlet, and the waste-pipe, of a springvalve, means connecting the said valve with the internal filter-pressure, and means operated automatically by said valve for reversing the flow of liquid through the filter-bed when the latter becomes foul, substantially as described for the purpose specified.

4. In a filter the combination with the filter-bed,the unfiltered-liquid inlet, the filteredliquid outlet and the waste-pi pe, of a springvalve, means connecting the said valve with the internal filter-pressure, and means operated automatically by said valve for reversing the flow of liquid through the filter-bed when the latter becomes i'oul and for restarting the lterin g after the filter-bed is cleansed,

` substantially as described.

5. In a filter the combination with the lter-bed,the unfiltered-liquid inlet,the filteredliquid outlet and the waste-pipe, of a slidevalve controlling the unfiltered-liquid inlet, a waste-valve for controlling the waste-pipe, a rod connecting the said slide-valve and waste-valve, and means for automatically operating said valves so as to close the unfilteredliquid inlet and open the waste-pipe when the filter-bed is foul, and to close the waste-pipe and open the unfiltered-liquid inlet after the filter is cleansed, substantially as described.

G. In a filter the combination with the filterbed,the unfiltered-liquid inlet, the filteredliquid outlet, the' Waste-pipe, and means for automatically reversing thel flow of liquid through the filter-bed when th latter becomes foul, of means located in the filtered-liquid outlet to restrict the backward flow of filtered liquid when the direction of the flow through the filter is reversed for cleansing purposes,. substantially as described, for the purpose specified.

7. In a filter the combination with the filter-bed,the unfiltered-liquid inlet,the filteredliquid outlet and the waste-pipe, of a slidevalve controlling the unfiltered-liquid inlet the filtered-liquid outlet and the waste-pipe, a piston, a closed cylinder containing said piston, a rod connecting said piston with the 'said slide-valve, a distribu ting-valve for controlling a supply of fluid under pressure to the said cylinder, and means for automatically operating the distributing-valve so as to reverse the piston and slide-valve when the filterbed is foul and to again reverse the piston and slide-valve after the filter-'bed has been cleansed, substantially as described.

8. In a filter the combination with the filterbed,the unfiltered-liquid inlet,the filteredliquid outlet, and the waste-pipe, of aspring- `valve controlling a liquid-supply pipe, means for adjusting the load on said valve,-means for controlling said valve by the internal filter-pressure, and means operated automatically by said valve for reversing the flow of liquid through the filter-bed when the latter becomes foul and for restarting the filtering after the filter-bed is cleansed, substantially as described.

9. In a filter the combination with the filter-bed ,the u n filtered-liquid inlet, the filteredliquid outlet and the waste-pipe, of a valvechamber, a valve controlling the outlet of said valve-chamber, a liquid-supply pipe connected to said valve-chamber, a closed cylinder, a piston in said cylinder, pipes respectively connecting the opposite ends of said cylinder with the inlet and outlet of the filter, a rod passing through the valve-chamber and cylinder and having the valve and piston attached thereto, an adjustable spring which tends to hold the valve closed, and means operated automatically by said valve for reversing the fiow of liquid through the filter-bed when the latter is foul and for restarting the filtering after the filter-bed has been cleansed, substantially as described.

l0. In a filter the combination with the filter-bed,the unfiltered-liquid inlet,the filteredliquid outlet and the waste-pipe, of a springvalve controlling la liquid-supply, means for adjusting the load on said valve, means for controlling the said valve by the internal filter-pressure, a chamber into which the valve discharges liquid when the filter-bed is foul, a float-chamber below the first-mentioned chamber, asiphon connecting the first-mentioned chamber with the float-chamber, a fioat in said fioatchamber, a siphon for emptying the float-chamber, and means automatically operated by said float for reversing the flow of liquid through the filter-bed when the latter becomes foul and for restarting the filtering after the filter-bed is cleansed, substantially as described.

IIC

valve discharges liquid when the filter-bed is foul, a oat-'chamber below the first-mentioned chamber, a Siphon connecting the firstmentioned chamber with the fioat-chamber,

an adjustable siphon for emptying said floatchamber, a oatin said fioat-chamber, a slide-` valve controlling the unfiltered-liquid inlet the filtered-liquid outlet and the waste-pipe,

and means connecting said fioat to the slidevalve so that the latter is automatically reversed When the filter-bed becomes foul and is again reversed to restart the filtering after the filter-bed is cleansed, substantially as described.

12. In a filter the combination with the filter-bed,the unfiltered-liquid inlet,the filteredliquid outlet andthe Waste-pipe, of a springf valve controlling a liqiiid-supply pipe, means for adjusting the load on .said valve, means for controlling said valve by the internal tilter-pressure,a chamber into which the springvalve discharges liquid when the filter-bed is foul, a oat-chamber below the first-mentioned chamber, a siphon connecting the first-mentioned chamber with the float-chamber, an adjustable siphon for emptying the float-chamber, a float in said float-chamber, a rod xed to said float, a lever connected to said float-rod, a slide-valve controlling the unfiltered-liquid inlet the filtered-liquid outlet and the waste\pipe, a` piston, a closed cylinder containing said piston, a rod connecting said piston with the slide-valve, a distributing-valve for controlling a supply of fluid under pressure t0 the said cylinder, a valve-rod on said distributing-valve, and a connecting-rod connecting said distributingvalve rod to the said lever, substantially as described for the purpose specified.

13. In a filter the combination with the filter-bed,the unfiltered-liquid inlet,the filteredliquid outlet and the waste-pipe, of a springvalve controlling a liquid-supply pipe,means for adjusting the load on said valve, means for controlling said valve by the internal iilterpressure,a chamber into Whichthe springvalve discharges liquid when the filter-bed is foul, a float-chamber below the first-mentioned chamber, a Siphon connecting the first-mentioned chamber with the float-chamber, an adjustable siphon for emptying the fioat-chamber, a fioat in said heat-chamber, a rod fixed to said float, a lever connected to said float-rod, a slide-valve controlling the unfiltered-liquid inlet, a closed cylinder, a piston in said cylinder,a Waste-valve for controlling the waste-pipe, a rod connecting the slide-valve the piston and the waste-valve, a distributing-valve for con trolling a supply of fluid under pressure to the said cylinder, a valve-rod on said distributing-valve, a con necting rod connecting said distributingvalve rod to the said lever, and a loatvalve in the filter-casing to admit air to the filter when the fiow of liquid is reversed for cleansing the iilter-bed, substantially as described for the purpose specified.

In testimony whereof I have hereunto set my hand, in presence of two subscribing witnesses, this 10th day of October, 1899.

WILLIAM PATERSON.

Witnesses:

FRED C. HARRIS, F. W. MCLELLAN. 

